<div id="btn-zommIn" title="放大" class="cesium-button  cesium-toolbar-button" style="display: inline-block;">
    <i class="fa fa-plus"></i>
</div>
<div id="btn-ZoomOut" title="缩小" class="cesium-button  cesium-toolbar-button" style="display: inline-block;">
    <i class="fa fa-minus"></i>
</div>